When did Britain decide to join the European Union?

The United Kingdom made its first application to join in 1961. It was quickly apparent that there was a danger of political isolation within Western Europe, Commonwealth states were rushing to do deals with the new bloc, and it had American support. This application was vetoed by the French Government in 1963 with a second application vetoed by the French again in 1967. It was only in 1969 that the green light was given to negotiations for British membership. The United Kingdom joined the European Economic Community (as it then was) on 1 January 1973 with Denmark and Ireland. This proved controversial at the time. The Labour party initially sought renegotiation of membership. This was toned down to requiring a referendum on whether the United Kingdom should remain part of the Community. This referendum was duly held in 1975 with a 67% vote in favour of continued membership.